Metal supplementation to anaerobic granular sludge bed reactors: an environmental engineering approach

The objective of this research is the optimization of essential metal dosing in upflow anaerobic sludge bed (UASB) reactors used for methanogenic wastewater treatment. Optimization of essential metal dosing in UASB reactors is a compromise between achieving the maximal biological activity of the biomass present in the reactor, while minimizing the costs of the supplied metal and the metal losses into the environment. The fate of metals in the anaerobic granular sludge is studied. The boundary conditions to keep a stable reactor operation are evaluated: Nutrient deficiency due to lack of essential metals versus toxicity in case of their excess. Finally, metal dosing strategies are evaluated. It is shown that the metal addition to UASB reactors and the methanogenic activity are related and, more important, this relation can be quantified